Boiler



J. J. DUFFY.

BOILER.

APPLICATION FILED APR. 30, I920.

Pa tented Apr. 4, 1922.

QEsxph fwljig 5 cwzwiew 1.]. DUFFY.'

BOILER.

APPLICATION FILED APR. 30. I920.

1,411,327. A Patented Apr. 4, 1922.v

3 SHEETS-SHEET 2.

H Qibymeg lfi J. I. DUFFY. BOILER. APPLICATION FILED APR. 30, I920- 1,41 L327, Patented Apr. 4, 1922.

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. UNITED STATES PATENT OFFICE.-

osm J. DUFFY, or CHICAGO, ILLINOIS; g

BOILER.

, Specification of Letters Patent.

Patented Apr. 4, 1922.

Application filed April 30, 1920. Serial No. 377,914.

Be it known that I, JOSEPH J. DUFFY, a citizen of the 'United States, residin I at Chicago, in thecounty of Cook and tate of Illinois, have invented a certain new and useful Improvement in Boilers, of which the following is a full, clear; concise, and exact description,'reference being had to the accompanying drawings, forming a part of this specification. v

invention relates to boilers, and is directed to improve principles of boiler construction which I' contemplate embodying in low pressure boilers for heating purposes; in high pressure boilers for power or other purposes; or in. boilers generally The fundamental, purpose of these improved: principles of boiler construction is to in crease the economy and efiiciency of boilers;

One of the particular objects of the invention', by which I aim to attain the above general object, is to create a circulation of the water whichin its general direction of flow is progressively counter to the flow of the gases, although concurrent with the flow' of the gases in each of the several heating sections. I More specifically stated, this general direction of' flow of the water is progressively downward, counter. to the'as cending flow of the gasesand 'is at the same time concurrent with the upward flow. of

the gases in each of the heating'sectionsnized by those skilled in the art, and resides "in having. the inlet water first pre-heated by the colder gases adjacent the exhaust flue, and then having the water progressively heated by circulating the same pro gressively counter to the flow of the gasesand toward the point of highest temperature until a maximum temperature is reached in" the fire gases adjacent the fire box. It

will be apparent thatthepresent construc-;

tion and arrangement; of the circulating. tubes by whichthis improved circulation is obtained alsohas application to hot water heaters as. well as boilers. p v Another objectof the invention, is to providea construction. of boiler, the interior of which is divided into two separate and distinct areas, namely, (1) a circulating zone wherethe water is first pre-heated and brought up to a temperature approaching that of the boiling point; and (2) a steam separating zone wherein the water is brought to a steaming temperature and steam generation is effected. The heated water in the circulating zone-is transferred into the steam separating zone intermittently or continuously at a, predetermined rate, this transfer being preferably from the hottest point in the circulating zone so that full benefit will be had from the pre-heated condition of the water therein. This. transfer of the heated Water between the two zones is preferably controlled by the Water -level in the separating zone, so that a sub-;

culating zone, and tendingto traptherein,

over into the separating zone.

Another object of the, invention is to pro:- vide a sectional construction of boiler whichcan be manufactered at small expense, and: which may be erected with facility and will permit of convenient removal and substitution of sections.

In the accompanying drawings illustrat-l,

' ing a preferred embodiment ofmy inven tion: v

Figure 1 is a front elevational view of my improved boiler; Figure '2 is a vertical sectional view through the same; t Figure 3 is a transverse sectional view through the-boiler; f

1 Figure 4 is a detail sectional view of the; float mechanism; and

Figure 5. is a diagrammatic illustration of the transfer pump and control mecha? nism therefor. for high pressure boilers, The construction of boiler illustrated in Figure 1 is designed for low pressure heat ing' purposes. such aslfor vapor steam systems' and other steam heatingsystem's. boiler may been'clo'sed in any suitahle man-n ne'r,v the arrangement illustrated consisting The.

. prevent upward passage of the flue gases of a brick setting having front and rear brick walls 6 and ,7 and removable side plates 8 and 9 for affording access to the interior of the boiler. The boiler enclosure is covered off by a top 10 of brick or heat insulating material. The removable side plates 8 and 9 are provided with a slab or facing of insulating material 8' andl) Referring to Figure 2, the circulating zone of the boiler comprises a plurality of heating sections 1111; the uppermost section being inclined upwardly from leftto right and the succeeding lower sections being alternately inclined in reverse directions in zig-zag relation. Each of these heating sections 11 comprises right and left hand headers 12 and 13, which extend transversely through the flue'area of the boiler, and which I are provided with a multiplicity of small circulating tubes 14 extending across the flue area. These tubes are arranged in spacedrelation from front to rear of the boiler, being welded to the headers 12 and 13. Above each series of tubes 14 and preferably resting thereon, is a baflie 15, constructed ofheat insulating material, which is preferably arranged to induce an upward circulation of the gases along the tubes of each section. To this end the lower edge of each baffle is extended up and over the top of the lowermostheader of its respective section so as to 1ntersect the endwall of the boiler casing and around the lowermost header, and the upper edge of each baffle adjacent the upper header of its section is cut off short of the header so as to provide flue areas around the outside of the header and between the circulating tubes 14 on theinside of the header, as indicated at 1616. Theheaders are spaced sufficiently from the side walls to permit free circulation of the flue gases around and about the headers.

The several sections 11 are supported in the boiler by extending the ends of the headers out through the front and rear walls (3 and' 7, which comprise the brick walls of the setting. At their rear ends (Figure the headers are closed off by threaded caps 17,

which thread over the outer ends of the headers. At their front ends the headers have circulating connection through elbows 18 and coupling unions 19, which maybe readily I coupled and uncoupled to permitof the disconnect the uppermost and lowermost headers of eachadjacent pair ofv sections, e. g.the first and second sections 11, beginning from the top", have their upper and lower headers 12-12 connected together,.the second and third sections have their upper and lower headers 13-13 connected together, the third and fourth sections have their upper and:

lower headers 12 connected together, and so ore-from which it will be observed that the several sections are all serially connected together for a progressively downward circu- '-l2Li Z1OI1 of the water.

The inlet to the boiler isthrough pipe 21 which has connection through elbow 22 with the lower header 13 of the top section 11. The six independent heating sections '11 constitute the circulating zone through which the water is first circulated before being admitted 'to the steam generating and separating portion of the boiler (to be hereinafter described). The closed circuit through this circulating zone is completed by a return connection consisting pipes 23 and 24, which connect the upper header 13 of the bottom section with the upper header 12 of the top section. These return pipes are preferably'situated' outside of the boiler enclosure, and have connection with. the headers 13 and 12 of the bottom and top sections respectively through the connections 25 and 26. The pipes 23 and 24 are connected by a T connection 27, this T connection being the. highest point in the circuit and being provided with a vent' 28 and vent valve 29 for venting air out of the system. The T connection 26, it will be noted, has communication through the end circulating connection 19 with the header 12 of the second section 11, so that the" return circulation in reality is into the bottom header 12 of the second section.

Directly below the sections 11constitut-i header 33 of relatively large dimension which functions as a steam space for receiv ing the steam from they tubes 32. The head ers 31 and 3 3are extendedthrough the front; and rear walls of the boilerand similarly to the headers 12 and 13' A steam freeing level is maintained in the series of'pipes 32 at sub stantially the point indicated, the upper ends of the tubes above this level and the header 33 constituting the steam collecting chai her. This steaming level is niaii'itaiiied by in termittently admitting heated water from the circulating, zone into the steaming section 30 when the level recedes thereimthis being accomplished through the instrumentality of a float mechanism 3 4 which con-j meets the T25 of the circulating system with the lower header 31 of the steaming section. This fioat mechanism is illustrated in detail in Figure 4, andjcomprises afloat chamber 35 in which is disposed a"relativel'y large float 3'6. The inlet to this float chant ber is through a pipe 37 which connects into the end of the T connection 25. The pipe 37 preferably connects with the circulating system at the T 25, inasmuch as the circulat- 41',- communicating with the inlet pipe 37.

The outlet from the float chamber is by way of pipe 42, which extends down from the bottom of thefioat chamber and has connection with a T connection 43. The T 43 is interposed in a pipe 44, which has connection at one end through an elbow 45 with the end of the, lower head 31 of the steaming section, and at the other end has connection" through a pipe 44' with the bottom of the projecting steam header 33. 1 The projecting end of this steam header 33 has connection through an elbow 47 or other suitable fitting. with a steam discharge pipe 48'. A gauge 49 indicates'the'eflective pressure in the steam discharge pipe 48. The water level in the steaming section 30 'is'in'dic'ated in a gauge glass 51, which has connection. at one end with the elbow 47 and at the other end has 7 connection in the return pipe 44. This pipe 44' functions primarily as a return pipe for returningthe condensation and any slight amount'of water dischargedinto the steam header 33 during rapid stear'ning,'this condensate: and discharge watersettling down through the pipes 44 and 44 and returning tothe lower header 31.

The boiler may be heated in any preferred manner.an oil or gas burner-52 being illustrated as discharging into the lower coinbusti'on area '53 through an air induction tube 54. The steam generating section- 30 is disposed in the combustion area. 53 with a. viewito having it utilize a large proportion ofthe efiectiv'e heat units. The section 30 1's provided with an upper bathe-55 for deflecting the'gases'fot combustion up along the tubes 32"and around the steam header 33 At its lower end the baflie 55 is extended over'the top of the header 31 to intersect with the'side wall 8 and close off this end" against passage of the ases, and at its upper end the bafile is cut s m of the header so astoj permit the gases to completely envelop the steam header, 'both on the outside between the. header "and "the" side wall and I onvthe' inside between the tubes32. .Afterv circulating through the devious passes be tween the-several sections 11 ofthe circulat ing zone the gases are exhausted through a stackf56" leading'fmm the top of the boiler settingy "Lag-ginger other suitable heatinsulating material may be applied to the circulating connections 19 which connect the ends of the headers of the circulating sections, and tothe'return pipes 23 and 24 of the circulating system as well as to the return pipes 44 and 44' of the steam generating section; or,

as an alternative constructiomthese pipes may be enclosed within the boiler enclosure or may be set into the wall thereof, where they will be immune to heat radiation. In this regard, I also contemplate a unit block construction built up of superposed, integral, block-shaped "castings which constitute in unit form, the four Walls of the boiler en" closure, the upper and lower headers, and the inclined tubes or heating passages; these block-shaped castings being so constructed that the boiler can be assembled by merely erecting the castings one upon the other, without necessitating end connections 19 and the like. v 1

The operation of the boiler is as follows: We shall assume that the boiler is employed in a vapor heating system, or in a one-pipe steam heating system. 7 The feed water enters the inlet pipe 21 under the gravity head from the vapor tank (in'the case of a vaporsystem), or under the city water pressure (in the case of a one-pipe steam system), and maintains a certain pressure in the circulating zone of the boiler at all times. The steam generatingzone fills with water until a predetermined level, as indicated, is reached, whereupon the float 36 rises and shutsoif further admission from the circulating Zone. The float 36 is designed with sufiicient capacity tofunctionagainst a considerable water pressure in'thecirculating zone. From the circulation of the gases, which are as indicatedby the large flowof the gases as indicated by the small direction arrows; As a result of this upward circulation created in the tubes of the v lower section, there will be induced a down; ward circulation of the colder water inthe" endcirculating connection 19, whichleadsto the lower header 12. The gases in rising through the flue openings 16 of the lower section pass along the under side of the next succe'edingsection and induce a corresponding upward circulation of the waterin this section-in augmentation of the circulation created in the lower sectionandin' the end connection 19 connecting the two sections."

This action of inducing an upward circula tion in theinclined circulating sections is repeated throughout the entire series ofsections, the buoyancy and the circulating pressure of the heated water decreasing the several sections compels a downward circulation through each of the end connections 19 to the next lower section, owing to the fact that the section-per se is primarily.

, the heat absorbing area as compared to the 'end connection, which receives littleor no heat, and also owing to the fact that the preponderating circulation in the lower section is in a direction away from the end connection and thereby induces a downward circulation in this end connection to take the place of themore buoyant water circulating upward from the lower end of the lower section. Hence it will be seen that a progressively downward circulation will be created by this upward flow of the water in each of the circulating sections, the heated water discharging from the lower end of the circulating zonethroughthe T connection 25 andrising through the return pipes 23 and24 to the upper end of the circulating zone, where it enters the header 12 of the second section 11 As steam is formed inthe steam generating zone of the boiler the water level in the tubes 32 recedes until the lowering ofthev float 36 unseats the'valve 39, whereupon the heated water from the circulating zone enters the tubes 32 and restores the level to its predetermined height. Thus, only a definite, predetermined quantity of water is exposed to the fire for steam generation at any one time. When a more rapid rate of steaming is required, the heated water is merely admitted to the steam generating zone at a faster rate, under the automatic control of the float valve. In ordinary heating boilers the effective pressure in the circulating zone will alwaysbe higher than in the steam generating zone so that the water will enter the section 30 immediately upon unseating of the valve 39. 1 It will be noted that the water in the steam generating zone is quiescent and that there are no pressures acting in rear of the water column in the steaming section 30 which might tend to discharge water with the steam; consequently there is an entire absence of priming effector water vaporin ing the rise and fall of the water levelin thefloat chamber 35, I contemplate connecting the top of the steamheader 33 with the top of the float chamber 35 through a pres-'.

sure equalizing pipe 60, which will insure uniformity of pressures acting upon each end of the Water column in the steam gen-- erating section so that the rise and fall-of the water level in the float chamber. will be immediately responsive to the rise and fall of the water level in the tubes 32., As Water is withdrawn from thecirculating zone to supply the steam generating zone, feed water is drawn into the boiler through the inlet pipe 21 and uppermost heating section 11. There is normally practically no circulation in the upper section 11 and consequently the feed water therein. is pre-heated in this section between periods of influx of feed water into the boiler, so that each quantity of feed water will enter the circulating zone in a pre-heated condition.v

For high pressure 1nstallat1ons,such as in power plants and the like, it is necessary to employ. a forced injection arrangement for forcibly injecting feed water into the circulating zone, or for forcibly injecting the heated water from thecirculating zone into,

the steam generating zone. I preferably employ thelatter method, and as illustrated in Figure 5,control the operation of the in j ector mechanism through electrical apparatus which is responsive to the fallof the,

water level in the steam generating section. In this embodiment, the lower header of the steam generating section has connection at its end with a water return pipe 62,'which comprises an upright section 62. threading into the bottom of the steam header 33.; Extending through the side wall ofthe pipe section 62 at substantially the 1 predeter 70 of which has connection withthe pipe 62 or other groundedpart of the boiler structure. reason of the water level in the pipe 62' being normally in contact with the electrode 64, and in this energized condition the relay maintains its armature 71 outof engagement with a back: contact 72, against the tension of the spring 73. The armature '71 and con- 7 The relay 67 is normally energized by.

tact 72 control a circuit, which in turn controlsthe operation of the injector. mechanism. This injector mechanism may consist.

of an electrically actuated steam injector, or

I a power driven force pump, preferably the latter, however, as indicated at 75. The

pump 75 .is an'ordinary force feed. reciproeating pump which is driven, through suit-- able reduction. gearing 7 6 from an electric motor 77 Oneterminal of the motor'77 has connection through wire 78. with the wire 70 of the" lighting circuit, the other terminal of the motor having connection boiler, the pipe 82 tapping into the circulating system at its lowest point through a T connection 83. The discharge port of the pump 75 has connection through the pipe- 84 with the connection 85 on the end of the lower header of the steam generating section. It will be obvious that when the water level in the steam generating zone falls below'its predetermined height the relay 67' will be de-energized by interruption of the circuit through the contact 64 and the winding 66, and that the electric motor '77 will be energized by the completion of the circuit thereof through the armature 71 and back contact 72; whereupon the operation of the injector pump 75 will withdraw heated water from the circulating zone and inject it into the steam generating zone until the predetermined level is restored and the relay 67 reenergized. It will be understood that this electrical control of the transfer of water between the circulating zone and the steam generating zone also has applicationto the low pressure form of heating boiler previously described. As exemplifying such adaptation I contemplate interposing an ordinary valve in the transfer pipe 37 in lieu of the fioatmechanism 34, and actuating this valve electrically by a solenoid or electromagnet under the-control of arelay 67 or under the direct electrical control of the contact c4. r w

It will be apparent that various modifications and rearrangement of parts may be made by those skilled in the art, but I intend these modifications and re-arrangements shall come within the spirit and scope of the appended claims.

Thus, current is t I claim:

1. In heating means, the combination of end headers and successive banks of'superposed circulating tubes extending between said headers, said headers defining separate. 1

manifold conduits connecting with the ends of said banks of tubes,-said banks of tubes being alternately inclined'in reverse directions, the high manifold conduit, of each bank of tubes being connected to the low manifold conduit of a lower bank of tubes, whereby the circulation is upward in each bank of tubes and'progressively downward from top to bottom of the series of tubes,

means connecting the several banks of tubesv in a closed circuit whereby a continuously recurring circulatlon 18 created through'the banks of tubes, and bafilemeans forming a zigzag heating flue winding between the banks of tubes.

2. In water heating means, the combination of a series of superposed water conduits alternately inclined in zig-zag relation, baffies forming a zigzag flue conduit between said water conduits, and circulating connections connecting the upper end of each Water conduit with thelower end of the succeeding lower conduit for producing an upward circulation in each of said water conduits, and a progressivelyfdownward circulation throughout the entire series of water conduits.

3. In combination, a plurality of superposed heating sections, each of said sections comprising horizontal end headers and a row of circulating tubes extending between said headers, thetubesand headers of each section-beingformed as an integral unit, the successive rowsof tubes being inclined in zig-zag' relation, means connecting the header at the upper end of each bank of tubes with the header at the lower end of the next lower bank of tubes, and bafiles de- 

